In April 2006, there was an “SP Fun Day” - G/SP region. All 17 SP SOTA summits were simultaneous activated, and each one had a S2S with each other one - apart from 2. But 134 S2S contacts out of a possible 136 wasn’t bad hi, and all within a 60 minute time window! I’m certain that there will have been 4 or more SOTA summits together on a single QRG several times in this event.
Other events have also stimulated many S2S contacts within a short time frame, such as the NP Fun Day, the G/LD youth hostel SOTA weekends, the GW/NW SOTA BBQ & camping weekends and the two International SOTA Weekends.
I do not know whether this happened already before, but the last sunday morning was a real SOTA highlights for me:
first I have had a S2S QSO with the happiest man in the world OE5HCE/p Christian after his marriage proposal to Sandra and her answer “yes, sure”.
After that OE5PEN/p Erwin, DL/ON9CBQ/p Franz and you DL/ON4UP/p Peter were calling in for a S2S QSO. Christian was so friendly to share “his” QRG with us, so we have had a nice chat between four summits OP and we could congratulate Sandra and Christian!
This was the first time that I could qualify a summit with four S2S QSO’s at the beginning of an activation. Thank you very much.
By the way, my 5.QSO was a S2S with GW4WSB/p Bill on GW/MW-014.
Therefore I think you are right, this was a very remarkable SOTA day indeed.